As is well known, there is software that visualizes communication states between a plurality of computers connected via the Internet protocol (IP) network. The computer that has obtained the communication state visualization function by the activation of this software receives a copy of packets flowing between the plurality of computers to be monitored and displays contents of the received packets as they are. In addition, the computer that has obtained the communication state visualization function displays information about a protocol and an address described in the packet after converting the information into a form that users can understand easily, or extracts and performs a statistical process on packets that satisfy a specific condition so as to display a chart or a graph thereof. In addition, the computer that has obtained the communication state visualization function may display a ladder diagram of a sequence of establishing a transmission control protocol (TCP) connection and communication of messages based on the received packet. Here, the message is reproduced by reconstructing segments remaining after an IP header and a TCP header are removed, and means a transmission unit on a communication layer on the upper level of the TCP.
The reception of the copy of packets flowing between the plurality of computers to be monitored is usually realized by a port mirroring function of a local area network (LAN) switch. The port mirroring function is a function of copying packets passing through a specific communication port so as to send out the copy from a mirror port. The computer in which the software described above has been installed is connected to the mirror port of the LAN switch to which all of the plurality of computers to be monitored are connected.
For instance, as illustrated in FIG. 13, an application server 21 that performs a business logic to which transaction management, session management, data processing, and the like are applied is disposed between a web server 11 and a database server 41 of a web three-tier system. In this web three-tier system, if the web server 11, the application server 21, and the database server 41 are incorporated in different machines 10, 20, and 40, respectively, a relay device (not shown) in an external network and a first network interface card (NIC) 15a in the web server machine 10 are connected to each other via the first LAN switch 60, a second NIC 15b in the web server machine 10 and a first NIC 25a in the application server machine 20 are connected to each other via the second LAN switch 70, and a second NIC 25b in the application server machine 20 and a NIC 40a in the database server machine 40 are connected to each other via the third LAN switch 80.
In the example illustrated in FIG. 13, when a hypertext transfer protocol (HTTP) interface (I/F) and the NIC on the lower level of the web client (not shown) communicate an HTTP message with an HTTP interface 12a and a first NIC 15a on the lower level of the web server 11, the first LAN switch 60 relays the packets that is fragments of the HTTP message. In addition, the first LAN switch 60 copies the relayed packet and transmits the copy to a communication state visualization function 91 in a machine 90 whose NIC 90a is connected to its own mirror port.
When an Internet inter-ORB protocol (IIOP) (a trademark of an object management group) interface 12b and the second NIC 15b on the lower level of the web server 11 communicate an IIOP message with an IIOP interface 22a and first NIC 25a on the lower level of the application server 21, the second LAN switch 70 relays the packets that are fragments of the IIOP message. In addition, the second LAN switch 70 copies the relayed packets and transmits the copy to the communication state visualization function 91 in the machine 90 whose NIC 90a is connected to its own mirror port.
When a structured query language (SQL) interface 22b and a second NIC 25b on the lower level of the application server 21 communicate a SQL message with a SQL interface 42 and the NIC 40a on the lower level of the database server 41, the third LAN switch 80 relays the packets that are fragments of the SQL message. In addition, the third LAN switch 80 copies the relayed packets and transmits the copy to the communication state visualization function 91 in the machine 90 whose NIC 90a is connected to its own mirror port.
Then, the communication state visualization function 91 illustrated in FIG. 13 receives packets from the first to the third LAN switches 60 to 80, and reconstructs the HTTP message, the IIOP message, and the SQL message based on the received packets so as to display the ladder diagram of communications of the messages as illustrated in FIG. 14.
In the ladder diagram, time bases of a web client machine (not shown), the web server machine 10, the application server machine 20, and the database server machine 40 are displayed in parallel. Then, an arrow indicating one message transmission is drawn from the time base of the machine that has sent the message to the time base of the machine as the destination. The arrows indicating the HTTP message, the IIOP message, and the SQL message are drawn so that a sequence of communications of messages (transactions) in response to a request from the web client machine.
Further, for example, an interval between end points of the arrows on the time base of the web server machine 10 clearly indicates a period of time Ta (seconds) from the time point when the HTTP message is received to the time point when the IIOP message is transmitted. In addition, for example, an interval between end points of the arrows on the time base of the application server machine 20 clearly indicates a period of time Tb (seconds) from the time point when the IIOP message is received to the time point when the SQL message is transmitted. Thus, a server machine that has been processing for a long period of time can be found.
The following is a related art to the invention.    [Patent document 1] Japanese Patent Laid-Open Publication No. JP 2006-011683